.bordered(@w:10px, @c: red) {
  border: @w solid @c;
  box-shadow: 0 0 0 0 red;
}

body {
  background-color: green;
  .bordered();
  a {
    color: red;
    animation: none;
    .bordered(1px);
  }
}
.btn {
  .bordered(5px, blue);
}
